John Curl's Blowtorch preamplifier part II

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Have fun Waly, it has already started. The bulk resistance is almost meaningless after a point, those guys made bespoke connectors out of large pure copper bars with the capability of applying serious clamping force for a reason.

No, I have already given up. Messing up RMS noise with noise density is already more than I can swallow before ejecting a pavement pizza.
 
I forgot to bring my earplugs to the Jacob Collier set on the 13th at the ill-named Hotel Cafe in Los Angeles (on the outskirts of Hollywood). But fortunately, the most demanding part of the evening was having to stand up for three hours straight. The SPLs were high but not ridiculous. When Arturo Sandoval played a guest solo he blew the roof off in his usual masterful fashion.

It was definitely the e ticket ride in town. Among other luminaries Quincy Jones was there. He got one of the very few seats, entirely appropriate. Toole was ill so couldn't make it, and I told him it may have been as well, as he doesn't like to stand all that long either.
Next time drop some acetyl-l-carnitine, n-acetylcysteine, alpha lipoic acid and a B complex. Preferably prophylactically if possible.
 
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I found a small company that sold me the complete work of a smps 1000w 100 euros. pcb. component link. cheap. easy to find. discrete component. PC40 toroidal. instruction for winding. absolutely everything. and smps. working after 1 year. it's free right?

Odd second post for someone, esp as same as the first post you made on another thread.
 
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Next time drop some acetyl-l-carnitine, n-acetylcysteine, alpha lipoic acid and a B complex. Preferably prophylactically if possible.
I already take acetyl-L-carnitine, alpha-lipoic acid, usually B vitamins, and a host of other things many mainstream doctors would assure me are a waste of money, on a daily basis. In the meantime I do not take statin drugs, blood pressure meds, antidepressants, and a host of other things that a$$holes like Paul Offit would prefer.
 
No, I have already given up. Messing up RMS noise with noise density is already more than I can swallow before ejecting a pavement pizza.

A quick survey showed flooded lead acid batteries at ~.1 Ohm series resistance and the best I could find for Li-ion was .025 Ohm. I know (at least I hope) Ed knows that no amount of averaging correlation etc. gets below that, there is no measuring some underlying battery noise in the absence of its own series resistance. So that places us at 20pV at best. 1pV is 60u Ohms not achievable in any practical situation.
 
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A quick survey showed flooded lead acid batteries at ~.1 Ohm series resistance and the best I could find for Li-ion was .025 Ohm. I know (at least I hope) Ed knows that no amount of averaging correlation etc. gets below that, there is no measuring some underlying battery noise in the absence of its own series resistance. So that places us at 20pV at best. 1pV is 60u Ohms not achievable in any practical situation.

????

Measuring the internal impedance of a battery is trivial. Look at the current SLA thread for folks showing noise well above that. It is from my point within reason to measure the noise under load for these battery packs to see if it rises much above the thermal noise of the internal impedance.
 
????

Measuring the internal impedance of a battery is trivial. Look at the current SLA thread for folks showing noise well above that. It is from my point within reason to measure the noise under load for these battery packs to see if it rises much above the thermal noise of the internal impedance.

Well you don't need rocket science or 1pV to do that. To be fair I have been thinking along the lines of a traditional voltmeter real time DC and all that as a general purpose instrument like the SQUID ones.
 
I already take acetyl-L-carnitine, alpha-lipoic acid, usually B vitamins, and a host of other things many mainstream doctors would assure me are a waste of money, on a daily basis. In the meantime I do not take statin drugs, blood pressure meds, antidepressants, and a host of other things that a$$holes like Paul Offit would prefer.
:cool::)

That well boost your immune system a bunch... esp higher doses of the B complex.

Give you a lot more energy as well.


-RNM
Those are targeted nutrients for hearing repair. Marshall Buck used n-acetylcysteine to good end. I use them too to battle loud sound event exposure. Now that I am on a FOK diet I need them less often.
 
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bring your own gullibility

6000 euro, I wish I could do this with a straight face. Imagine just standing there and taking peoples money.
The Altmann BYOB amplifier

Does anyone know what chip amp it is? Someone speculated Tripath but this was doubted be someone else. Given the absence, at least that I could see, of output inductors, it must be someone's class AB part.

Looking at the picture I can't imagine the BOM running more than 20 USD. The potentiometer looks particularly cheap. I suppose the battery connectors are a bit expensive. Perhaps the spruce is expensive, particularly when possessed of such amazingly fine-tuned acoustical properties. If you remove the amp board it could be used to slice bread for those on a low-carb diet.

But then he has all that R&D to amortize.

EDIT: I wonder if it would throw a monkey wrench into the subjective evaluations if one pointed out that a ponderable extended object like a lead-acid car battery has a significant capacitance to the outside world?
 
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Well you don't need rocket science or 1pV to do that. To be fair I have been thinking along the lines of a traditional voltmeter real time DC and all that as a general purpose instrument like the SQUID ones.

Mentioned before this is play. Magnetic amplifier is a toy to try. A pretty much forgotten technology. The other technique that popped up was positive feedback to increase the noise.

Using George's cite you can just stack batteries to get an easy to read result. As I often repack UPS units, not a problem to make two stacks of ten SLA 12 volt batteries. Negatives get connected and measure across the positive end. If charged that way should have almost no DC. The noise result will be sqrt(20) times one battery

Now FeLiPO units are cells. 4 of them will make a decent battery but require a monitor circuit. So that has to be included to make a fair comparison.
 
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MQA digital recording-playback appears to the the answer to my digital problems. Got to try it.
With DRM? It existed in an earlier form from Keith and Phlash- as HDCD. Meridian rerolled the whole thing using the same concepts as MQA except they have some issues with the encode process where they aren't sharing and want money. The more curious aspect is that they can bulk encode with the MQA process, something that doesn't make sense if its correcting for source errors and they do not know the source chain. Some of the best critical discussion is here: Archimago's Musings: MEASUREMENTS: MQA (Master Quality Authenticated) Observations and The Big Picture... Archimago's Musings: MEASUREMENTS / IMPRESSIONS: Meridian Explorer2 Analogue Output - 24/192 PCM vs. Decoded MQA.
 
EDIT: I wonder if it would throw a monkey wrench into the subjective evaluations if one pointed out that a ponderable extended object like a lead-acid car battery has a significant capacitance to the outside world?

I liked the discussion of sonics vs state of charge. Yawn, what a pile of doggie do.

The plywood and spare Harley parts TT, stunning.
 
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